Add #error if __NR_vfork required but not defined.

Improve test of error code.

diff --git a/sysdeps/unix/sysv/linux/arm/vfork.S b/sysdeps/unix/sysv/linux/arm/vfork.S
index 0630c7f..bba1a54 100644 (file)
--- a/sysdeps/unix/sysv/linux/arm/vfork.S
+++ b/sysdeps/unix/sysv/linux/arm/vfork.S
@@ -38,8 +38,7 @@ ENTRY (__vfork)
        b       PLTJMP(C_SYMBOL_NAME(__syscall_error))
 # else
        /* Check if vfork syscall is known at all.  */
-       ldr     a2, =-ENOSYS
-       teq     a1, a2
+       cmn     a2, #ENOSYS
        bne     PLTJMP(C_SYMBOL_NAME(__syscall_error))
 # endif
 #endif
@@ -50,6 +49,8 @@ ENTRY (__vfork)
        cmn     a1, #4096
        RETINSTR(movcc, pc, lr)
        b       PLTJMP(C_SYMBOL_NAME(__syscall_error))
+#elif !defined __NR_vfork
+# error "__NR_vfork not available and __ASSUME_VFORK_SYSCALL defined"
 #endif
 
 PSEUDO_END (__vfork)